A leg used for a chair in aircraft is shown in FIG. 7. The leg is generally made of Aluminum and is a V-shaped member having three first recesses (130) to reinforce the structural strength and a hole (131) defined through each end thereof to connect the leg to the seat frame (not shown). Referring to FIG. 8 which shows that a pair of legs (110) are cut from an Aluminum plate (11). The legs (110) are then machined to obtain the recesses (130) and the holes (131) as disclosed in FIG. 7. The final process is the heat treatment process to make the legs (110) have the desired stiffness. However, the conventional method involves the following shortcomings:
1. To cut the two legs (110) from an Aluminum plate (11) wastes too much material. It is estimated that only 40% of the material is utilized. PA1 2. The crystalline structure of the Aluminum plate (11) is broken when cutting the two legs. This could weaken the structural strength of the legs. PA1 3. The steps involve the use of a complicated skill and take a long time so that the manufacturing cost cannot be reduced. PA1 step 1: preparing a metal ingot; PA1 step 2: bending the metal ingot into a V-shape; PA1 step 3: forging the V-shaped member from step 2 to include at least one first recess in at least one side thereof and two second recesses defined in two ends thereof, with flash being formed on the periphery of the V-shaped member during the forging process; PA1 step 4: roughly removing the flash from the V-shaped member formed in step 3; PA1 step 5: applying a first heat treatment process (T4 process) to the V-shaped member resulting from step 4; PA1 step 6: removing the flash left on the V-shaped member in step 5 and adjusting the V-shaped member to have the precise desired shape, and PA1 step 7: applying a second heat treatment process (T6 process) to the V-shaped member in step 6.
The present invention intends to provide a method for manufacturing the legs of a chair with a simple process that saves time and money. The present invention uses a metal rod to manufacture the leg of a chair so as to reduce the wasted metal and effectively resolve the shortcomings of the conventional method for manufacturing the legs of a chair.